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The Ptolemaic is based on the Greek philosophy that all the objects in the sky must follow circular motion in one form or another. With the Earth supposed at the centre, the planets' movements were quite complicated and each planet needed a good number of epicycles.
The idea of epicycles is that you have a large circle (the deferent) and then a small circle (the epicycle) whose centre moves round the deferent. Then the planet travels round that epicycle.
Extra epicycles were required to represent what we now know as the planets' elliptical orbits and the inclination of the orbits to the ecliptic.
The basic idea of the deferent and epicycle is easily explained in terms of Venus's orbit. We now know that with the Sun at the centre, Venus and the Earth travel round circular orbits in 225¾ and 365¼ days with radii of 1.000 units for the Earth and 0.723 units for Venus (we are assuming circular orbits to make the example easier). This is the basis of the Copernican heliocentric model.
If you choose to consider the Earth is at the centre, this motion is exactly replicated by having a deferent with radius of 1.000 units round the Earth, and on it is an epicycle with its centre going round in 365¼ days. The epicycle has a radius of 0.723 units and Venus travels round the epicycle in 225¾ days. This is the basis of Ptolemy's model (in the Ptolemaic model the Sun also went round the Earth in 365¼ days, but at a larger radius beyond the 'sphere' of Venus).
Both these models represent the position of Venus as seen from the Earth with equal accuracy. That is still the case when the extra epicycles are added for ellipticity, inclination et cetera.
So the issue between the Ptolemaic model (geocentric) and the Copernican model (heliocentric) was not accuracy but whether the Earth or Sun was at the centre. There was no way at that time of deciding which was correct, but Copernicus's model did not have such violent motion of Venus, which was one reason Galileo preferred it.
Eventually Kepler came up with an alternative system, and that is the one used today, because it is backed up by later theoretical discoveries of the law of gravity and the laws of motion.
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What is the celestial bodies?
Astronomist
How did people thousand of years ago use the movement of celestial bodies to help them?
Thousands of years ago, people observed the movement of celestial bodies, such as the sun, moon, and stars, to guide their agricultural practices, navigation, and timekeeping. They used the changing positions of these bodies to determine planting and harvesting seasons, as well as to create calendars. Additionally, celestial navigation helped early explorers and traders find their way across oceans and deserts. This knowledge laid the foundation for early astronomy and contributed to the development of various cultures.
What is the studyof celestial bodies called?
astronomy
What celestial bodies begin with a?
Some celestial bodies that begin with the letter "A" include asteroids, auroras, and the planet Venus (known as the "Evening Star").
What was ptolemys evidence for his space theory?
Ptolemy put the Earth at the center of his model of the universe , and said that the Sun , the moons , the planets ,the asteroids , comets , and meteors orbit the Earth and the Earth was the center of the universe.
What is the source of force behind the movement of celestial bodies in the universe?
The source of force behind the movement of celestial bodies in the universe is primarily gravity.
What is the Equal Transit Theory and how does it explain the movement of celestial bodies in the universe?
The Equal Transit Theory suggests that all celestial bodies move at the same rate through space, regardless of their size or mass. This theory helps explain the consistent and predictable movement of celestial bodies in the universe, such as planets orbiting around stars.
What is the impact of acceleration in space on the movement of celestial bodies?
The impact of acceleration in space on the movement of celestial bodies is that it can change their speed and direction of motion. This acceleration can be caused by gravitational forces from other celestial bodies or by propulsion systems on spacecraft. It can affect the orbits of planets, moons, and other objects in space, leading to changes in their trajectories and positions over time.
Is space relative in terms of the movement of celestial bodies?
Yes, space is relative in terms of the movement of celestial bodies. This is described by Einstein's theory of relativity, which explains how the motion of objects in space is influenced by the curvature of spacetime caused by massive objects like planets and stars.
Do paleontologists study celestial bodies?
No Astronomers study celestial bodies
What limitations are there in astrophotography when it comes to capturing images of celestial bodies?
Limitations in astrophotography include atmospheric conditions, light pollution, equipment quality, and the movement of celestial bodies. These factors can affect the clarity and quality of images captured.
Information about dates on which certain celestial bodies were seen?
Dates on which celestial bodies were seen
What are the key principles of au physics and how do they apply to the study of celestial bodies?
The key principles of physics, such as gravity, motion, and energy, are crucial in understanding celestial bodies. Gravity governs the movement of planets and stars, while motion helps explain their orbits and rotations. Energy plays a role in the processes that occur within celestial bodies, like nuclear fusion in stars. By applying these principles, scientists can analyze and predict the behavior of celestial bodies, leading to a deeper understanding of the universe.
Does mars have celestial bodies?
no it does not
What is the celestial bodies?
Astronomist
What is the relative angle between two celestial bodies?
The relative angle between two celestial bodies is the angular separation between them as seen from a specific point of observation. This angle is measured in degrees or radians, and it helps astronomers determine the position and movement of celestial objects in the sky.
What is the professions celestial bodies?
Astronomist
